The most annoying thing about classical crossover is the pretensions, both upmarket and down. Did Kiri Te Kanawa really think she could pass herself off as Miss Broadway? (She has all but recanted some of the show albums she made in the 1980s). Did RCA recording executives really think rock fans wanted to improve their minds with a wildly misbegotten disc titled Symphonic Music of the Rolling Stones?

Now, what used to be crossover is a variation on remixing, reloading and mash-upping. In contrast to the artificial missions of crossover discs (like bringing opera to the masses or something equally hopeless), a more casual let's-try-it mentality has Rufus Wainwright beginning concerts with a French-language Hector Berlioz art song - in his own voice and manner, just because he wants to.

From the other end of the telescope, the physically challenged German art-song baritone, Thomas Quasthoff, won't be passing himself off as some sort of Euro Paul Anka on March 7 when he sings jazz (of sorts) with guitarist Chuck Loeb and percussionist Peter Erskine at Carnegie Hall, a spin-off of his new Deutsche Grammophon disc, The Jazz Album: Watch What Happens. Even on the Mormon Tabernacle Choir's recent entry into the glitter zone with Showtime!: Music of Broadway and Hollywood, the singers aren't trying to tell the world that they "got rhythm."

But what, oh what, are we going to do with Sting? The perpetually glowering leader of the reunited Police has long been a model rock star. He never became stuck in the same groove, kept all his teeth, and didn't get fat. But at 10 p.m. tomorrow on WHYY-TV's Great Performances, he sings repertoire that might strain the credulity of the most adventurous mash-up DJ - the Elizabethan songs of John Dowland, in a documentary titled Sting: Songs from the Labyrinth.

Here, as on the companion Deutsche Grammophon CD titled The Journey & the Labyrinth, Sting treats the music like blues with starched collars - with lutes rather than acoustic guitars. Conceptually, it's thoroughly defensible. Though Dowland is now sung mostly by cultivated voices, who's to say that Elizabethan singers weren't more like Sting? So why is this Great Performances segment as embarrassing, in its own way, as when Luciano Pavarotti lost his place while warbling "Singin' in the Rain" during a Three Tenors concert?

The Sting documentary mixes songs and biographical discussions among experts about Dowland's many travels (some of which may have included spying for Queen Elizabeth) and the nature of his melancholic temperament. Lutenist Edin Karamazov is fabulously watchable because his absorption in the music is so complete. Sting is always on hand, offering his two cents. And the problem is?

OK, we classical nerds should be grateful that charismatic rock royalty is making a state visit to our retro little fiefdom. But nothing can disguise the fact that Sting comes off as fundamentally boring. His two cents are worth just that. You tire of his singing, and even of his succession of snazzy shirts and sweaters. Near the end of the documentary, he dons a Druidic cape and walks around the landscaped labyrinth on his estate. It's supposed to be a meditation, but the activity seems so meaningless that you ask what world he's living in.

Beyond the obvious, determining what's truly missing here requires a look at what German baritone Quasthoff and the Mormon Tabernacle Choir (did we ever imagine putting them in the same sentence?) are doing right.

Like Sting, they remained themselves. Anything else would be dishonest. The Mormons, for example, try to make Broadway glamour seem inspirational, and with that ultra-rich vocal sound applied to "No One's Going to Hurt You" from Sweeney Todd, they often succeed. The Germanic precision of Quasthoff's clean, sonorous voice in, say, "My Funny Valentine," brings its own, sharp-focus perspective to music made famous by the more spontaneous vocalism of Ella Fitzgerald.

But even when Quasthoff and the Mormons are engaged in an artistic meeting of apples and oranges, their commitment to the musical otherness creates a friction that makes their odd-match wrongness possibly more interesting than if they had been more right. They might ultimately generate more mixed notices than Sting because they offer more to disagree with.

Clearly, Sting likes Dowland. Like many pop stars (Paul Simon, for example), he takes a reportorial, almost passive approach toward lyrics that says the passion is in the writing, not in the singing. But Sting's uninflected, vibrato-free, elongated vowels - they sound like electronic droning - reduce Dowland to a series of abstract sounds that substantially obscure the music's content and meaning. In effect, Sting doesn't seem engaged enough to create friction with anything.

The remix mentality is, by nature, provisional. Even the most intriguing meetings of unlikely artistic minds may not have any larger implications, especially if they don't meet a vital need in their respective cultures. They're answers to questions nobody asked, anomalies that aren't more than the sum of their parts. That disposability is refreshing for classical folks, who are used to having everything etched in granite. But the provisional doesn't justify the superficial. Even if the artistic meeting is a one-night stand, it has to have the heat of one.
Contact music critic David Patrick Stearns at dstearns@phillynews.com. Read his recent work at http://go.philly. com/davidpatrickstearns.

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